Dutasteride is an androgen blocker that's approved to treat male pattern hair loss (also known as androgenetic alopecia) in Japan and South Korea. It's also FDA-approved for the treatment of benign prostate hyperplasia - commonly known as an enlarged prostate. This oral medication is generally thought of as a stronger version of finasteride, so it's sometimes used off-label to treat androgenic alopecia.
Dutasteride's strength is also considered its weakness. Historically, it's been assumed that if it's stronger than finasteride, it may also have the potential to produce more systemic side effects. (1) In order to reduce the risk of such side effects, an alternative formulation, topical dutasteride, is currently being explored.
